The present invention relates to a data inputting device for inputting data to a computer, word processor or similar data processor and, more particularly, to a data inputting device for inputting coordinates and images.
A data inputting device for the above application has been proposed in various forms in the past. For example, the data inputting device is implemented as a coordinates inputting device or pointing device for inputting coordinates, or an image inputting device for inputting images.
The pointing device may consist of a tablet for detecting coordinates on the basis of capacity coupling, and a pen. Various kinds of pointing devices heretofore proposed each has a particular principle of operation. Japanese Patent Laid-Open Publication No. 4-45481, for example, teaches a device which applies shift pulses to scanning lines extending in an X direction and a Y direction, thereby generating loop currents. This type of device detects the coordinates of an intersection which a pen is positioned, on the basis of the pulse application timing and the pen detection timing. Japanese Patent Laid-Open Publication No. 63-184823 discloses a device capable of determining the position of a pen by use of optical fibers arranged in the vertical and horizontal directions, and a pair of image sensors. Japanese Patent Laid-Open Publication No. 4-369016 proposes a device having a pen whose point issues light, and a protection glass. When the pen is pressed against the protection glass, the coordinates on the glass are detected by a bidimensional CCD sensor. Japanese Patent Laid-Open Publication No. 4-195624 teaches a device having transparent electrodes arranged in the X and Y directions, and an electronic pen having a capacity detecting circuit at the point thereof. This device sequentially applies a frequency of several hundred hertz to the transparent electrodes, and detects a change in the capacity via the detecting circuit while displaying it on a liquid crystal display which plays the role of a tablet at the same time. Further, Japanese Patent Laid-Open Publication No. 63-257020 discloses a device having a tablet implemented as a transparent vibration transfer plate, and a vibration pen. After the vibration transfer plate has been laid on a document, the vibration pen is put on the plate. The vibration of the pen is transferred via the plate to a plurality of sensors arranged on the plate, so that coordinates can be detected.
On the other hand, a handy scanner which is a specific form of the image inputting device has a plurality of rollers, a linear image sensor, and an encoder. The rollers roll on the surface of a document. The image sensor has a width covering an image reading width and is so positioned as to adjoin the document. The encoder is used to sense the movement of the image sensor in the subscanning direction.
A particular inputting unit has been developed for each of the pointing devices and image inputting devices described above. However, modern image processors with advanced functions allow data to be input therein in various modes Moreover, there is an increasing demand for an implementation capable of switching the modes rapidly by, e.g., splitting a screen. This brings about a problem that when both of the two different devices are required, they must be put on a desk together, occupying a substantial space. In addition, the two inputting units must be held by hand alternately or must be replaced with each other on the desk, resulting in inefficient manipulation.
Further, in the conventional handy scanner, the encoder responsive to the movement in the subscanning direction, and rollers for stabilizing the travel of the scanner are arranged around the linear image sensor. Hence, the scanner cannot be reduced in width, i.e., length in the subscanning direction. As a result, the scanner conceals the image reading portion over a substantial width including the line being input. This prevents the operator from accurately seeing the portion being read. Moreover, data available with the encoder built in the scanner are not absolute coordinates representative of the reading surface, but they are relative coordinates, i.e., amounts of rolling or movement. Hence, once the scanner is brought out of contact with the reading surface, it is necessary for the operator to match the beginning of the portion to be read next to the end of the portion previously read. This is further aggravated by the great width of the handy scanner.